This invention relates to an apparatus for turning over and exchanging lead and trail edges of sheets, and more particularly, to an improved full productivity high performance inverter apparatus that is adjustable in size to accommodate different sheet lengths.
Although a sheet inverter is referred to in the copier/printer art as an "inverter", its function is not necessarily to immediately turn the sheet over (i.e., exchange one face for the other). Its function is to effectively reverse the sheet orientation in its direction of motion. That is, to reverse the lead and trail edge orientation of the sheet. Typically, in inverters as disclosed here, the sheet is driven or fed by feed rollers or other suitable sheet driving mechanisms into a sheet reversing chute. By then reversing the motion of the sheet within the chute and feeding it back out from the chute, the desired reversal of the leading and trailing edges of the sheet in the sheet path is accomplished. Depending on the location and orientation of the inverter in a particular sheet path, this may or may not also accomplish the inversion (turning over) of the sheet. In some applications, for example, where the "inverter" is located at the corner of a 90.degree. to 180.degree. inherent bend in the copy sheet path, the inverter may be used to actually prevent inverting of a sheet at that point, i.e., to maintain the same side of the sheet face-up before and after this bend in the sheet path. On the other hand, if the entering and departing path of the sheet, to and from the inverter, is in substantially the same plane, the sheet will be inverted by the inverter. Thus, inverters have numerous applications in the handling of either original documents or copy sheets to either maintain or change the sheet orientation.
In the field of reprographic machines, depending on the architecture, the finisher setup, and paper path configuration, some simplex printing may require an inverter subsystem in order to deliver copy sheets in 1- N orientation when the sheets are removed from an output tray. One prior art inverter for accomplishing this task is shown in FIG. 1. which shows the conventional configuration of a reversing roll inverter. In order to minimize the straight through (non-inverting) paper path length and to handle sheet sizes from B5 to A3 (sheet lengths: 7" to 17"), this inverter may require the copier/printer to operate in a skip-pitch mode for sheets larger than A4 sizes. This impacts significantly the throughput of larger sheets that require inversion.
The present invention aims at providing an adjustable baffle reversing roll inverter which can adapt to all sheet sizes to maintain full machine productivity. Baffles of the inverter are interleaved so that they can easily be extended or collapsed to accommodate sheets of different lengths.